Introduction: One of the common psychological problems among dormitory students is depression and its symptoms. The aim of this study was to examine the effectiveness of group behavioral activation (BA) on depression and cognitive-behavioral avoidance in University student.Methods: This study is a experimental design study with a pretest/posttest and follow-up with a control group. Sixty dormitory students of Andimesh were randomly selected by availability sampling method and randomly assigned to a BA tratment group (n=30) and a wait-list control group(n=30).The treatment group received eight-weekly BA sessions. The Beck depression inventory and The Cognitive–Behavioral Avoidance Scale (CBAD) were used as outcome measures, before and after the intervention with a one-month follow-up. Data analyzed with multivariate analysis of covariance.Results: The results showed that behavioral activation therapy was effective in reducing symptoms of depression (P<0.01, F=11.26) and cognitive-behavioral avoidance (P<0.05, F=7.02).Conclusions: Results showed that behavioral activation therapy on depression symptoms, and cognitive-behavioral avoidance was effective. Given the efficacy of BA treatment on depression symptoms and cognitive-behavioral avoidance, BA therapy could be an alternative for the clients that seek for effective and short-time treatment in university counseling centers.